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Rainbow Electronics AT89C5131 User Manual

Page 73

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73

AT89C5131

4136A–USB–03/03

the CAPP bit enables the positive edge. If both bits are set both edges will be
enabled and a capture will occur for either transition.

The last bit in the register ECOM (CCAPMn.6) when set enables the comparator
function.

Table 55 shows the CCAPMn settings for the various PCA functions.

Table 54. CCAPMn Registers (n = 0-4)

CCAPM0 - PCA Module 0 Compare/Capture Control Register (0DAh)
CCAPM1 - PCA Module 1 Compare/Capture Control Register (0DBh)
CCAPM2 - PCA Module 2 Compare/Capture Control Register (0DCh)
CCAPM3 - PCA Module 3 Compare/Capture Control Register (0DDh)
CCAPM4 - PCA Module 4 Compare/Capture Control Register (0DEh)

Reset Value = X000 0000b
Not bit addressable

7

6

5

4

3

2

1

0

-

ECOMn

CAPPn

CAPNn

MATn

TOGn

PWMn

ECCFn

Bit

Number

Bit

Mnemonic

Description

7

-

Reserved
The value read from this bit is indeterminate. Do not set this bit.

6

ECOMn

Enable Comparator

Cleared to disable the comparator function.

Set to enable the comparator function.

5

CAPPn

Capture Positive

Cleared to disable positive edge capture.
Set to enable positive edge capture.

4

CAPNn

Capture Negative

Cleared to disable negative edge capture.
Set to enable negative edge capture.

3

MATn

Match

When MATn = 1, a match of the PCA counter with this module’s
compare/capture register causes the

CCFn bit in CCON to be set, flagging an interrupt.

2

TOGn

Toggle

When TOGn = 1, a match of the PCA counter with this module’s
compare/capture register causes the CEXn pin to toggle.

1

PWMn

Pulse Width Modulation Mode

Cleared to disable the CEXn pin to be used as a pulse width modulated output.

Set to enable the CEXn pin to be used as a pulse width modulated output.

0

CCF0

Enable CCF Interrupt

Cleared to disable compare/capture flag CCFn in the CCON register to
generate an interrupt.

Set to enable compare/capture flag CCFn in the CCON register to generate an
interrupt.